Disclaimer: This unit was sent to me by Kefine. All opinions of this unit are my own and remain independent. As always with audio, preferences and ear shapes vary, so your experience may differ.
You can purchase the Kefine Klean SV via these channels (non-affiliate links):
Introduction
The original Klean built a solid reputation in the budget scene thanks to its clean tuning and strong price-to-performance, so the Klean SV has some expectations to live up to. I don’t have the original Klean on hand for a direct A/B, so this review focuses purely on how the SV performs on its own.
Pros
✔️ Solid all-metal build
✔️ Very comfortable for long
sessions
✔️ Clean, balanced tuning
✔️ Tight and controlled bass
✔️
Smooth, non-fatiguing treble
✔️ Easy to drive
✔️ Triple nozzle
system adds flexibility
✔️ Solid accessory set for the price
Cons
❌ Not for bassheads
❌ Overall tuning may feel too safe for
treble lovers
❌ Nozzle differences are subtle, not dramatic
What’s in the box
- Kefine Klean SV IEMs
- Stock cable (3.5mm version in this case)
- 6 pairs of silicone eartips
- 3 pairs of tuning nozzles (Black, Silver, Gold)
- Carry case
- Documentation
IEM Shell Design
The Kefine Klean SV has metal shells with a matte finish. On the faceplate are geometric grid pattern printed in black and the KEFINE branding printed also in black. In hand, the shells feel solid with clean machining, though there is a visible seam line where the shell halves meet.
There’s also a small exposed screw on each shell, which adds to the mechanically assembled feel rather than looking purely glued together. The pressure relief vent sits near the nozzle, and the L/R markings in printed black are clear and easy to see. The recessed 0.78 mm 2-pin sockets look properly aligned and secure.
At around ~9.4 g per side with a ~6.0 mm nozzle, the fit should be friendly for most ears. The shape follows a familiar ergonomic contour that sits naturally in the ear, and the low-profile design helps the shells stay secure once properly seated. During longer sessions, the size and weight balance well enough that they don’t feel intrusive.
Stock Cable
The stock cable is a lightweight silver-plated copper cable that looks clean and feels nicely flexible in hand. It doesn’t fight you when coiling, and during actual use it stays out of the way.
The plug housing, Y-split, and chin slider are all metal, which gives the cable a slightly more premium feel in daily use. The splitter carries subtle KEFINE branding, and the plug itself is also branded, which is a nice touch. Overall fit and finish look tidy. The cable itself weighs around ~17.4 g, which is light enough that it never caused any noticeable pull during my use.
You also get clear L and R markings on the connectors, which makes orientation quick and foolproof when plugging into the shells. The preformed ear hooks hold shape well without being overly rigid.
In terms of build and appearance, the 3.5 mm and 4.4 mm cables are essentially identical. The only real difference is the termination.
Carry Case
The included case is a simple gray fabric zip case with the white Kefine brand printed on the lid. It measures roughly ~99 mm x ~71 mm x ~30mm. The outer shell feels firm enough to give just basic protection inside a bag, and the zipper runs smoothly.
Inside, you get a simple but functional layout with a soft-lined compartment on one side and a small mesh pocket on the other for storing spare tips or nozzles. There is enough room to fit the IEM and cable without having to force things in.
Stock Eartips
The included eartips come in two silicone styles. Even in the same small size, they feel noticeably different in firmness despite having very similar bore sizes. The lighter gray tips feel softer and more pliable, making them very easy to seat in the ear. The darker gray tips use a slightly thicker inner stem (roughly ~0.1 mm thicker by my estimate), which makes them feel more structured overall.
The darker gray tips gave me a tighter seal and slightly better isolation, while the lighter gray set felt a bit more relaxed in fit. I personally ended up preferring the small dark gray tips since I found them to be more comfortable. Of course, your mileage may vary.
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General Usage Impressions
The shells fit my ears well
overall and sit securely once properly seated. With the correct eartips,
isolation is excellent. In my case, the small dark gray silicone tips gave
me the best seal and comfort during longer listening and gaming sessions. I
did not experience any pressure buildup, and the shells stayed firmly in
place even during extended use.
Although my bundle included the
3.5 mm cable, most of my listening was done using the optional 4.4 mm cable
Kefine provided. The cable is lightweight and unobtrusive, with no
noticeable tugging.
Sound Impressions
The Klean SV had the silver nozzle
preinstalled so I started with that. For consistency, I stuck with the same
small dark gray tips for all listening. Once I had the right tips on, it
basically disappeared in my ears.
Nozzle swaps are audible, but
don’t expect three completely different IEMs. The core tuning of the Klean
SV stays consistent. To my ears, silver and gold are especially close, with
the biggest shift happening when moving to the black nozzle. Most of the
changes live in the upper mids and treble, while bass and overall tonality
stay largely intact.
For gaming, I used Overwatch 2. It’s a
competitive game with a lot going on sound-wise, good directional cues, and
solid mixing, so it’s useful for checking things like separation and clarity
when it gets chaotic.
Silver Nozzle (Balanced / Default)
- Tuning: This is the safest all-rounder. Clean, balanced, and very easy to listen to.
- Bass: Nicely controlled. Sub-bass shows up when the track asks for it, but it doesn’t try to dominate the mix. Mid-bass stays tidy.
- Mids: Vocals come through naturally with decent body. Nothing sounds shouty or hollow to my ears.
- Treble: Smooth and polite. There’s enough detail to keep things clear without turning sharp.
- Technicalities: Imaging is dependable for the price. Stage width is about average, not cramped but not huge either.
- Gaming: Easy to track footsteps and positioning. Stays fatigue-free during long play sessions.
Gold Nozzle (Brighter / More Energetic)
- Tuning: Slightly more energetic up top compared to silver, though the difference is subtle.
- Bass: Still controlled and clean, with similar quantity to silver.
- Mids: Upper mids come forward a bit more, giving vocals and effects extra presence.
- Treble: Carries a bit more bite and sparkle versus silver. Not harsh to my ears, but the most lively of the three, though the gap vs silver is small.
- Gaming: Can help with clarity and edge definition, but more sensitive listeners may prefer silver for long sessions.
Black Nozzle (Smoothest / Most Relaxed)
- Tuning: The smoothest and most relaxed of the three.
- Bass: Feels slightly fuller due to the more laid-back top end, though still controlled.
- Mids: Vocals sound a bit smoother and less forward compared to gold.
- Treble: Noticeably more tamed. This is the least spicy option and the easiest on the ears.
- Gaming: Very comfortable for long sessions, though you trade a bit of crispness in positional cues.
Preferred Nozzle
Personally, I kept coming back to the silver nozzle.
To my ears, it hits the best balance between clarity and comfort without leaning too warm or too sharp. The gold nozzle is there if you want a bit more energy up top, while the black nozzle is the smoothest and most relaxed of the three. But for my daily music listening and longer gaming sessions, the silver nozzle just felt the easiest to live with.
Final Thoughts
The Kefine Klean SV is easy to like if you prefer a safer, more easygoing tuning. It doesn’t chase boosted bass or sharp treble peaks. Instead, it goes for a clean, balanced presentation that works well for daily listening. Comfort is solid, isolation is strong with the right tips, and I had no issues running this for longer sessions.
The triple-nozzle system is a nice bonus. The differences aren’t night and day, but they are enough to slightly fine-tune the sound depending on your preference. For me, the silver nozzle hits the sweet spot and is where I’d recommend most people start.
At around $49, the Klean SV comes across as a mature, no-nonsense daily driver. If you’re looking for huge bass or sparkly treble fireworks, this probably isn’t the one. But if you want something comfortable, balanced, and easy to listen to for hours, the Klean SV is a very solid pick in its price bracket.
Technical Specifications
- Driver: 10mm DLC dynamic driver
- Frequency Response: 20 Hz – 20 kHz
- Impedance: 32 Ω ±15%
- Sensitivity: 107 dB ±3 dB
- Distortion: ≤1% (at 1 kHz)
- Shell Material: Metal alloy
- Cable: Silver-plated copper cable (~1.2 m), available in 3.5 mm, 4.4 mm, or USB-C variants
- Connector Type: 0.78 mm 2-pin
- Plug Type: Depends on selected bundle (3.5 mm / 4.4 mm / USB-C)
Sources Used
- PC + FIIO K11 R2R
- Snowsky Echo Mini
- Xiaomi 13T + Letshuoer DT03
Songs Used
- オトノケ - Otonoke / Creepy Nuts
- bury a friend / Billie Eilish
- goosebumps / Travis Scott
- Giorgio by Moroder / Daft Punk
- Ain’t It Fun / Paramore
- Hello / Adele
- ピースサイン - Peace Sign / Kenshi Yonezu
- Ref:rain / Aimer
- 革命道中 - On The Way / AiNA THE END
- Love poem / IU
- Perfect Night / Le Sserafim
- SLOW DANCING IN THE DARK / Joji
- Sparkle - movie ver. / Radwimps